Crystal structures of two new six-coordinate iron(III) complexes with 12-bis(diphenyl­phosphane) ligands

摘要

Structural characterization of the ionic complexes [FeCl2(C26H22P2)2][FeCl4]·0.59CH2Cl2 or [(dppen)2FeCl2][FeCl4]·0.59CH2Cl2 (dppen = cis-1,2-bis­(di­phenyl­phosphane)ethyl­ene, P2C26H22) and [FeCl₂(C₃₀H₂₄P₂)₂][FeCl₄]·CH₂Cl₂ or [(dpbz)₂FeCl₂][FeCl₄]·CH₂Cl₂ (dpbz = 1,2-bis­(di­phenyl­phosphane)benzene, P₂C₃₀H₂₄) demonstrates trans coordination of two bidentate phosphane ligands (bis­phosphanes) to a single iron(III) center, resulting in six-coordinate cationic complexes that are balanced in charge by tetra­chlorido­ferrate(III) monoanions. The trans bis­phosphane coordination is consistent will all previously reported mol­ecular structures of six coordinate iron(III) complex cations with a (PP)₂ X ₂ (X = halido) donor set. The complex with dppen crystallizes in the centrosymmetric space group C2/c as a partial-occupancy [0.592 (4)] di­chloro­methane solvate, while the dpbz-ligated complex crystallizes in the triclinic space group P1 as a full di­chloro­methane monosolvate. Furthermore, the crystal studied of [(dpbz)₂FeCl₂][FeCl₄]·CH₂Cl₂ was an inversion twin, whose component mass ratio refined to 0.76 (3):0.24 (3). Beyond a few very weak C—H⋯Cl and C—H⋯π inter­actions, there are no significant supra­molecular features in either structure.